> On 15 Jun 2015, at 12:12, Timothy Williams <[log in to unmask]> wrote:
> 
> People
> 
> 
> The good news is the publisher has accepted a book for publication. The bad news is I must Americanise - sorry, Americanize - the spelling.
> 
> How do I find a word ending in -our and replace it with -or?
[...]

Congratulations!
I suggest you change the language setting of the entire document from English (British) to English (U.S.).
Then let the spell checker do the “corrections”.

Hamid